STATUS REPORT: ALIGNMENT OF COLLIMATORS P. BESTMANN /O. ABERLE Collimation Working Group 26/09/2011

Overview  Situation today  Planned for Winter stop 2011/12  To be done in LS 1: 2013/14  To be done for LS2  Questions and Discussion 26/09/ CWG

Situation today 26/09/ CWG  Alignment in general:  Lower support part is aligned in the tunnel (with a dummy collimator (1/10 in weight);  Every collimator is prepared on surface to reference values Flange centre is the reference Aligned to the three supporting points Alignment transferred to fiducials on top of the collimator  Phase 1 installed and running since 2 years  Checks with beam based alignment procedure twice a year  Three versions:  Ring collimators in IR 3 and 7 (for remote handling and survey)  Ring collimators with “low” dose levels, not remote handling  Transfer line collimators (no plug-in system)

Situation today 26/09/ CWG  In March 2011, some collimators have been identified to need re-alignment. (an angular misalignment >1.9mrad on TCLA.A7R7.B1, TCTH.4L2.B1 and TCSG.A5L3.B2).  Reasons identified as:  conflict with adjacent vacuum chamber  Installation protection added on the support  IR extremities, dead end extrapolation

Situation today 26/09/ CWG  IR 3 and IR 7, warm section  TCSM locations prepared: 1. Base support installed 2. Cables up to the last few meters ready (No BPM!) 3. Rack space reserved, has to be reorganized 4. Vacuum replacement chambers ok TCSM + TCS slots

Situation today 26/09/ CWG  IR 7 is prepared for TIM manipulation  IR 3 will be equipped equally (stretched wire, additional targets)  Re-alignment upon request, two smoothening campaigns since first installation  LHC Smoothing should be followed by systematic collimator realignment in the future  All installed supports are “pre-aligned” but all installed new collimators need to be checked

Situation today 26/09/ CWG EMPTY PHASE II TCSM SLOT (30 IN TOTAL) PHASE I TCSG SLOT

Situation today – IR 2 26/09/2011 CWG 8 Current situation 4L2, part of VACSEC A4L2.C Insertion of a TCTVA Arc 1-2 IP2: ALICE Collimator areaID800 area Courtesy Eric Page

To be done in WS 2011/12 26/09/ CWG  IR 2 (if ECR is approved)  2 new TCTVA’s (TCLP collimators)  Layout change with new alignment (ca. 40 m on each side)  Use of mobile cryo-protections

To be done in LS 1: 2013/14 26/09/ CWG  IR 3 in 2013/14 (combined betatron/momentum cleaning in IR3 )  8 locations of phase 2 (TCSM) ok  Use Scraper location for additional TCP, Layout modification (Cooling and cables ok, supports and vacuum chambers to do)  IR 7 in 2013/14  22 locations to be equipped with phase 2 plug-ins. Alignment of supports for phase2.  Points to work on:  Pull cables for BPMs (IR3, other points, TCT?)  Work on flow rate/distribution for the final system (flow-fix?), upgrade of CV pumping system.  Auto retraction – clutch?

To be done in LS 1: 2013/14 26/09/ CWG  Produce and install cryo-protections?  IR 6 (Beam dump line modification (TCDQ, TCS...later?)  2 new TCSP’s  BPM cables  Start replacing TCT’s with TCTP’s (with BPM), IR with priority?  Pull cables for BPM’s to defined positions?

To be done/prepared for 2017? 26/09/ CWG  IR 1 and 5  4 TCLP’s (at Totem location)  Install supports, alignment  Produce and install cryo-protections? Mobile as for IR 2?  Replace all TCT’s with TCTP’s (with BPM)  Replace other collimators with BPM version  Cryo-solution?

Questions and Discussion 26/09/ CWG  Number of new collimators to be produced?: What type?  Change scraper locations (2) in IR 3 to TCP? Integration Change scraper locations (6) in IR 7 to hollow ebeam-lense?  Integrate TCT‘s into the Layout (IR 2 under study, IR 6, IR 8?)  Remove Roman Pots and install TCLP‘s to Point 1 and 5. When?  Keep and align Phase 2 slots?  Transfer lines?  Dump line?

Questions and Discussion 26/09/2011 CWG 14  Any alignment related observations during operation?  Tolerance for realignment IR7 and IR3 (OP needs vs. RP)  What can be compensated by the collimators (transversal offsets, rotations)  Requests for LS1